1. Field of the Invention
The present invention relates to an ink spraying device for a print head and, more particularly, to a device for receiving ink stored in an ink-jet print head and spraying the supplied ink when electric energy is applied.
2. Discussion of Related Art
A printing apparatus using ink performs printing by spraying ink stored in its print head through an ink spraying device. The ink spraying device receives the ink stored in the print head and ejects it onto paper when electric energy is applied. This kind of device includes a type using a membrane layer separating a heating chamber and an ink chamber.
A conventional ink spraying device using such a membrane layer is integrally formed with an ink spraying chip. The chip is made by forming a plurality of heating chambers on a silicon substrate, forming a membrane layer (which may include more than one membrane) on the heating chambers, and then forming a plurality of ink chambers on the membrane layer. A nozzle plate is then fixed to the thus-formed chip to complete the assembly.
To fix the nozzle plate to the ink spraying chip, the ink chambers of the chip and the nozzles of the plate must be precisely aligned using an alignment key formed on the chip's surface and carefully viewed through a microscope. In doing so, human error is introduced, causing an offset which impedes the advance of ink droplets out through the nozzle and thus diminishes the sharpness of the printing result. Therefore, a precision assembly step is required in aligning the nozzle plate with the ink spraying chip, which hinders productivity. For example, if the misalignment exceeds a maximum tolerance of .+-.1 .mu.m, the assembly is deemed defective.